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Dual P-Mag manifold pressure adapter

GalinHdz

Well Known Member
Anybody know where to get an aluminum dual manifold pressure adapter to connect two P-Mags? I have a plastic one similar to these from an auto parts store but would prefer a metal one instead.

ehc11_primary.jpg


:cool:
 
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same here

looking for something similar as well. If you have a manifold pressure sensor and dual pmags you need either two Ts or a 4-way adapter, and I've only been able to find plastic ones so far.
 
I use the push-in "Y" connectors that are used for pitot/static systems. They are behind the baffles, so the temps aren't extreme, and have worked fine for years. Also makes it really easy to disconnect and blow in a single tube to time both P-Mags simultaneously.
 
TS Flightlines

I had TSFlightlines alter my MP line between the #3 cylinder head and the FW with a TEE inserted in the line. He even clocked the fitting for me.
It made a nice install. Ran a seperate black hose from each PMag over to the fitting.
 
looking for something similar as well. If you have a manifold pressure sensor and dual pmags you need either two Ts or a 4-way adapter, and I've only been able to find plastic ones so far.
It sounds like there might be a small market for something like this. Maybe we can get TSFlightlines to make a few metal "T" and "Y" connectors and have them available for purchase. Something like these but in metal.

47338-007.jpg



47353-007.jpg


:rolleyes:
 
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This is what I used -

http://www.aircraftspruce.com/catalog/hapages/alummanifoldfit.php?clickkey=6557

I needed 3 manifold pressure outputs, 2 for the Pmags and another for the MAP sensor.

I mounted one of the "1 IN, 4-OUT" blocks on the firewall. I installed 2 nylon elbows - one for each Pmag, screwed the MAP sensor directly into the block and plugged the unused output port.

When I check the Pmag timing, it's easy to disconnect both lines and plug them into a simple Y adapter that I keep in my tool box.
 
Galin---we've actually improved on things. Email me and I'll send you a pic.
( Dont know why I didnt think of this before)

Tom
 
It sounds like there might be a small market for something like this. Maybe we can get TSFlightlines to make a few metal "T" and "Y" connectors and have them available for purchase. Something like these but in metal.

47338-007.jpg





:rolleyes:

If you are going to use a line that can be pushed onto a barbed fitting, what is wrong with a nylon fitting?
 
Tom question

Are you stocking these Grainger tees ? Grainger is a little cranky to deal with.
An MAP sensor adds another T and three more failure points. A 4 port metal component as mentioned, would be ideal if anyone wants to build some. Tom built me braided tube from the prime port on #4 with two nipples for Pmags. One with three for MAP also would be perfect.
 
Dual PMag tee

dual%20PMag%20tee_zps8sznfctv.jpg
Figured out how to post these.
First pic is the first version. Effective, but ugly, and labor intensive. Set up for 2 PMags. Could cap off 1 port for single PMag. The outlet hose routed to the MAP sensor, or the pressure manifold.

2nd pic. AN Tee with a 910 union to make it a 4 port tee. MANY configurations possible depending on the builder. This particular one has 2 AN826-3D tees with a AN910-1D union. Supply port from the engine, 2 branch ports to the PMags, outlet port to the MAP sensor. WE use teflon hose for the supply and outlet hoses as shown by the AN hose ends here. The 2 branch ports are -3 hose ends and can use the PMag supplied hose, or teflon hose adapted to the PMags. Maybe not as compact as the handmade version, but much easier. The added bonus for guys that initially have 1 PMag with a AN824-3D or 4D tee, you can remove that tee, and install the dual tee, and add 1 hose for the other PMag. This eliminates the need for a new hose assembly, or modifying one that you have.

I chose the -3 version to simplify the plumbing. Alot of guys use -4 hose for the MAP senders. Thats ok too---With a -4 tee, just use a -3/-4 stem to reduce the size for the PMag, or the sensor. The ID of the -3 stem is .079. We havent seen any adverse readings due to line pulses.

WE 'may' decide at some point to make these from 1 piece or bar stock. It would make a more compact unit, and eliminate the union. BUT, for the time being, this is easy. NOT plastic, brass, nylon, and uses threaded connections.


MAP%20hose%20for%20PMags_zpssvqcarwd.jpg


http://i1316.photobucket.com/albums/t620/tsflightlines/dual PMag tee_zps8sznfctv.jpg

Tom
 
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Tom asked me to post the second picture here.

This is the way that Tom and I do Dual PMAG setups.

Dual%20PMAG.jpg



We are currently working on a 14A Dual PMAG setup and will post a completed installation picture once setup. As Tom mentioned, we can work in both -3 and -4 and also can use jump size fittings to retain smaller hose while still utilizing some -4 hardware that may already be installed in the aircraft.
 
I found standard barbed tubing connectors in stainless steel at McMaster-Carr.

You can see it in the lower left corner of the picture.
IMG_3142-M.jpg


The tubing is silicon and the little clips also came from McMaster.
 
Yepp there are lots of ways to do this. Some guys didnt want a barbed connection. Thats why we changed ours to the AN Tees

Tom
 
Pulse Damper

I also added a pulse damper in the MAP line to smooth out pressure variations. I used an "Gauge Vibration Damper" from McMaster Carr P/N 3820K12. It has a .008" orifice and has worked very well. My manifold pressures are rock solid which helps in the timing with the P-Mag.
 
I use tees from irrigation dripper lines. Inexpensive, light, and durable. Nothing wrong with plastic in this application - if it fails, who cares?

When I see braided lines and aluminum block manifolds for this I have to wonder if you guys are building airplanes or farm equipment? Think and build light!
 
Michael, yep thats true. Some extra weight involved for sure, certainly more that a plastic and vacuum hose. Was just the idea of how to plumb 2 PMags and a MAP sensor. Yep--the SDS ignition solves that problem too!
Tom
 
Yep--the SDS ignition solves that problem too!
Tom

Well, not really. I have my dual Pmags, my dual CPI and now my new SDS EFI system MAP plumbed with dripper tees. I also use them on my pitot static system, but that's another thread.

No doubt your braided lines are absolutely bulletproof! But I like to remind people that this kind of weight adds up. Where I work, ounces matter on 60,000 pound airplanes. I can't help it!
 
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